Primary care physicians reluctant to prescribe prostate cancer prevention drug
■ A new survey says they don't know that finasteride is used for chemoprevention. Urologists fear the drug could raise the risk of tumors.
Physicians have not been quick to prescribe finasteride to men as a way to prevent prostate cancer, according to a new study.
A 2003 New England Journal of Medicine study showed a 25% reduced risk of prostate cancer when the drug was used. But 64% of urologists and 80% of primary care physicians said they never prescribe finasteride for chemoprevention, according to a study in the September issue of Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Assn. for Cancer Research. The study was published online Aug. 10.
When asked why they didn't prescribe finasteride as a preventive tool, 52% of surveyed primary care physicians said they did not know it could be used for chemoprevention. Among urologists, 55% said they were concerned that it would increase the risk for high-grade tumors (link).
An editorial that accompanied the 2003 NEJM study noted a 27% increased risk in high-grade tumors when patients took finasteride as a preventive medication. However, a 2008 report in Cancer Prevention Research said finasteride did not increase the risk of such tumors; it just made the tests available for the tumors more sensitive (link).
The new study showed that 34% of primary care physicians and 66% of urologists believed the benefits of finasteride for prevention outweighed or equaled its risks.
Researchers surveyed 464 primary care physicians and 302 urologists in the Veterans Health Administration. They also evaluated trends among prescriptions for finasteride filled within the VHA between January 2000 and December 2005. Doctors were encouraged to use finasteride for benign prostatic hyperplasia with symptoms not relieved by other drugs.
The data showed that physicians were prescribing finasteride more often, but "the change did not seem to be due to increased use of finasteride for chemoprevention," the study concluded.
Chemoprevention has been studied for other cancers, including breast and colorectal cancers, but physicians have not adopted it widely.
"There will probably be increasing attention to this topic. Right now, physicians don't have good tools to know who is at risk and who might benefit," said internist and preventive medicine specialist Linda S. Kinsinger, MD, MPH, a study author and chief consultant for preventive medicine at the VHA's National Center for Health Promotion and Disease Prevention in North Carolina.
Better tools need to be created to determine which patients would be most likely to benefit from chemoprevention, she said, adding that the medications being used need to be as safe as possible.
"We are asking people who don't have a condition to take a medication. That is a high bar," Dr. Kinsinger said.
Even something as common and inexpensive as aspirin being used as a chemopreventive agent would raise issues about the bleeding it could cause, she said.